Ultra Running Hub Boise, ID, United States · Saturday, May 9, 2026
Fixed Distance 50 mi
Boise Greenbelt Relays
Race completed
72 km Distance
not publishedn/a Climbing
3.6 est Grit · Challenging
Calculated from 72 km alone — the organiser has not published an elevation profile. Read 3.6 as a floor, not a verdict.
What the course asks
Time limit 8 hours
6:40 min/km average. Firm. Sustained running. Long aid-station stops will cost you. Climbing is unpublished, so this pace is a ceiling on the effort, not a measure of it. Among the tightest 50 mi cut-offs we track. Measured against 455 races of the same distance. Cut-off calculator →
Field size ~3 Tiny. You will run alone for most of it.
DUV results for the 2025 edition (45mi) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Typical conditions, May
Daytime high 21°C
Night low 7°C
Rainfall Mostly dry
Daylight 14 h 27 m of light
Regional 2001-2020 average for May — NASA POWER, grid elevation 1055 m. Not a forecast.
The Aid Station
Course-specific beta from the community
With trail terrain, choose a shoe with moderate cushioning for optimal performance.
Gear for this race
Chosen for 72 km of trail.
- Trail Running Shoes72 km of trail — cushioning that is still there in the last quarter.
- Race Nutrition72 km of self-supported fuelling between aid stations.
- Hydration VestsFlask capacity for 72 km, without the bounce.
- GPS WatchesBattery life first — a 72 km day outlasts most full-GPS modes.
Course Notes
45 miles looping the entire span of the Boise River Greenbelt through central Boise, Garden City, Eagle, and Southeast Boise.
Similar races
Other 50 mi trail ultras, closest in distance first.